A series of studies are being conducted to determine the following: l. The relationships between auditory processing deficits, speech perception skills, attention disorders, and speech and language development in hyperactive boys, with and without learning disorders; 2. The effects of stimulants on the speech, language and communicative skills of language disordered hyperactive boys; 3. Whether auditory processing disorders in hyperactive boys with and without disorders in speech, language and reading respond similarly to the administration of dextroamphetamine; and 4. Whether the effects of stimulant drugs on auditory processing disorders in language impaired children are related to the effects of stimulants on language processing and speech fluency.